Re: [Wxlua-users] Thinger. A DX7 editor for SysEx data transfer to DX7, FS1R etc.

[John L. <jla...@gm...>]

On 6/26/05, The Doctor <the...@bl...> wrote:
> I've just seen my first wxLua crash.
>=20
> WXLUA caused a stack fault in module WXMSW254_VC_WXLUA.DLL at 016f:100d10=
eb.

Oops. :(

> It happens consistently, as a result of using X:SetEventHandler(PANEL), w=
here X is a button or other control whose event handling is set elsewhere f=
or common handling of mouse clicks. The program is running ok as far as I k=
now, until the crash is invoked by changing the OS colour scheme. (I discov=
ered this while changing it to see the effects of using wx.wxNullColour.) I=
 commented out all the new code to eliminate things until the bug didn't ha=
ppen, then looked at what addition would alone be enough to cause the crash=
 when the OS scheme was changed, and it's definitely that X:SetEventHandler=
(PANEL) bit. Even with NO code affecting colours by explicit demand, this h=
appens.


I don't think your SetEventHandler(otherWindow) trick will work
without some serious c++ testing.You're probably breaking the chain of
handlers, hence the segfault. However, you may want to explore
PushEventHandler, but I bet you have to Pop it before the window is
destroyed.

What you're doing sounds a little strange, it doesn't make sense to
get the left button press on a wxButton, just get the
wx.wxEVT_COMMAND_BUTTON_CLICKED or if you want to disable the button
use button:Enable(false). Remember, wxWidgets wraps around the native
library and if that doesn't provide a function, neither does wxWidgets
(but they do try to smooth things out as much as possible). I would be
pleasantly surprised if a wxButton emitted a left down event for
example.

In terms of double clicks, it's always down, up, double IIRC.

Finally, FRAME:GetEventHandler():ProcessEvent(event) merely takes the
event you get in a child window, so you've got to set a handler for
it, and then asks the FRAME to handle it as if it was meant for it
(you're on your own doing this for key and mouse events since
wxWidgets may use them as well for some controls and won't expect them
from child windows). It would be best to simply call a common function
to handle the event for all windows if this is what you really want.

Good luck,
    John Labenski